Expandable computer board with dual shield housing solutions

ABSTRACT

A compact computer system board  10  comprises dual shield expansion zones  11, 12,  expansion connectors  113, 123  which can be connected to expansion boards. Once a expansion board is connected to the expansion connector  113  ( 123 ) in the shield expansion zone  11  ( 12 ) to extent the application of the system  10 , the shield metal housing cover  20  will be mounted above the shield expansion zone  11 ( 12 ). The shield expansion house formed by shield expansion zone  11 ( 12 ) and shield metal housing cover  20  isolates the electromagnetic interference between expansion board and the outside surrounding. The shield metal housing cover  20  as well as the shield expansion zone  11  ( 12 ) is the heat sink of the expansion board inside. The shield expansion housing solutions guarantee the system processing high reliability and stably in the limited space of the system board. Dual expansion housing solutions especially eliminate the cross interference with high heat sink ability under the situation when there are two radio frequency application expansion boards installed on to the system board.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of the Provisional PatentApplication Ser. No. 60/256,414 filed Dec. 18, 2000.

BACKGROUND

[0002] 1. Field of Invention

[0003] This invention is concerned with a computer system board,specifically a computer system board with dual shield housing solutionsfor critical environment applications.

[0004] 2. Description of Prior Art

[0005] It is known in the art of the regular Personal Computer (PC) andindustrial PC system board design, expansion slots are one of the keymechanisms on the board. They provide the hardware expandability of thesystem board. On a regular PC system board, ISA, PCI or PCMCIA slot canalways be found. PC-104's interfaces were introduced to be the mainexpansion standard for stackable industrial PC. To expand hardwareapplications, you can simply insert the compatible add-on cards into theslots on the system board. There is no strictly requirement on the sizeof a regular PC system board. Electronic components always generate heatand EMI. In the prior art of the PC, in order to eliminate theinterference and get better heat dissipation, certain spacing and sizeis required. To avoid EMI or heat issues, the system board is usuallydesigned in bigger size. But when the size of equipment is limited, thesize of system board is therefore limited. Thus the interference amongthe system board and the expansion boards increases. Whole system becameunstable, if no interference proof means is implemented.

[0006] When applying a system in a particular space limited application,it's hard to shield the electromagnetic wave interference and dissipatethe heat among the boards. So, regular design PC cannot be used in manyapplications, which need to meet the requirements of criticalenvironment. They may cause malfunction of the system for the timebeing.

[0007] Furthermore in some special applications, the interactiveinterference between the expansion boards and the system board is verystrong because of one or more radio frequency circuit boards involved.If there is not proper shield among the system board and the expansionboards, the system even cannot work.

[0008] Obviously, better solution is needed.

SUMMARY

[0009] The present invention provides the solutions which can getexcellent system board expandability in a limit space. The computerboard is designed for critical application circumstance. On this board,there is plurality of shield expansion houses.

[0010] The shield expansion housing solutions comprise an expansionzone, and a special shield metal housing cover with heat sink thatcovers the whole expansion zone after an expansion board is installed onto the system board. The expansion zone is a large ground plate of thePCB with connectors, which can connect with the add-on expansion board.

[0011] The shield metal housing cover as long as the shield expansionzone works together to conduct the heat generated by the expansion boardsealed inside, and, also shields the electromagnetic wave interferencebetween the expansion board and outside house. In my example, dualshield expansion houseing design with high heat sink especiallyeliminates the cross RF interference under the situation when there aretwo expansion boards doing radio frequency applications which areinstalled on to the system.

OBJECTS AND ADVANTAGES

[0012] Accordingly, several objects and advantages are achieved byproviding shield expansion houses on the system board of my invention:

[0013] 1) to provide highly stable and reliable applications of acomputer system board in a limited space by the shield expansion housingsolution of current invention;

[0014] 2) to use the shield metal housing cover as well as the heat sinkto provide high heat dispatching capability for the expansion board;

[0015] 3) to shield the electromagnetic wave interference among theexpansion board and the system board.

[0016] The forgoing features and advantages of the present invention canbe appreciated more fully from the following description, withreferences to the accompanying drawings in which.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017]FIG. 1 is a diagrammatic view of a system board design with thepresent invention.

[0018]FIG. 1A is a cut away side view of the system board taken alongline A-A of FIG. 1; and the side view of the expansion board, the shieldmetal housing cover and the add-on extra heat sink.

[0019]FIG. 2 is an enlarged view of the shield metal housing cover andthe expansion board.

DESCRIPTION—PREFERRED EMBODIMENT

[0020]FIG. 1 is a diagrammatic view of a system board design with thepresent invention. As shown in this embodiment, the computer systemboard 10 comprises a PCB 13, a processor 14, the connector 16(optional), other ICs 15,17 and expansion zones 11 & 12. The connector16 makes it possible for the system level expansion with other systemboards (not shown). Through this connector 16, more system boards can bestackable, thus it allows more expansion boards to fit into a particularspace and can process more applications.

[0021] On the system board 10, two shield expansion zones 11, 12comprise shield areas 112, 122 which are part of ground copper cladlaminate on the PCB with insulation; soldering zones 111&121, which canbe soldered together with a shield metal housing cover (referring toFIG. 2 the shield metal housing cover 20); and expansion connectors 113,123. Once the shield metal housing cover 20 is mounted on to the shieldexpansion zone 11 or 12, they can form a complete shield house with heatsink feature. The expansion boards connecting with the system boardthrough the expansion connectors 113 or 123 process the accordingapplications while they are isolated from electromagnetic waveinterference with the electronics outside the house. Meanwhile,electronics sealed inside the house have a good heat distributionenvironment.

[0022]FIG. 1A is a cut away side view of the system board taken alongline A-A of FIG. 1; and the side view of the expansion board, the shieldmetal housing cover and the add-on extra heat sink. As shown, theexpansion board 21 with connector 212 can be plugged into the expansionconnector 123 and mounted on to the system board 10. The components 215& 216, which need high heat distribution, have the heat conductor blades213 &214 on them. After the expansion board 21 is mounted on the systemboard 10, the shield metal housing cover 20 can cover the shieldexpansion zone 12 and be mounted on the system board also. The heatconductor blades 213 and 214 touch the shield metal housing cover 20 andconduct the heat from the IC 215 and 216; thus, the shield metal housingcover 20 becomes the heat sink of the whole expansion board. For heavyduty expansion board, which may generates more heat, and add-on extraheat sink 22 can be attached on to the shield metal housing cover 20 toprovide extra heat distributing ability for the expansion board.

[0023]FIG. 2 is an enlarged view of the shield metal housing cover andexpansion board. As shown in this embodiment, the shield metal housingcover 20 is an open metal box with four small soldering edges201,202,203 and 204, which can be soldered on to the soldering zone(referring to 111 or 121 of FIG. 1) of the system board 10. This formsthe complete shield house for the expansion board 21. In some specialcases, there may be holes need on the shield metal housing cover inorder for some of the circuit of the expansion board 21 to extend out ofthe shield metal housing cover. The expansion board 21 is an individualelectronic circuit board, which can perform certain functions; forinstance, a LAN card to provide networking functions for the systemboard. The expansion board 21 comprises a PCB 211 and a connector 212that can be connected to the expansion connector (referring to 113 and123 of FIG. 1) in the shield expansion zone (referring to 11 and 12 ofthe FIG. 1). Once the expansion board is sealed in to the shield house,the airflow inside the house is the heat conductor for all thecomponents. On the PCB 211, there are ICs 215,216,217, and 218. Some ofthem (215 and 216) need heat sink to make sure they work normally. Sothe heat conductor blades 213 and 214 are added on to them 215 & 216 toprovide better heat distribution. An add-on extra heat sink 22 canalways be added on to the shield metal housing cover 20 when better heatdistribution is required.

CONCLUSION, RAMIFICATIONS, AND SCOPE

[0024] Accordingly, the reader can see, I've provided a computer systemboard with dual complete shield expansion housing solutions. With thePCB structure of the current invention, the complete system board hasmore compact space and whole system is easier to fit into smaller space.With the shield expansion housing solution of the current invention,more applications can be processed reliability and stably on the systemboard with no interference as well as good heat dissipation. Dual shieldexpansion housing design especially benefit to eliminate the crossinterference with high heat sink ability under the situation when thereare two radio frequency application expansion boards installed on to thesystem board.

[0025] Although the description above contains much specificity, theseshould not be construed as limiting the scope of the invention but asmerely providing illustrations of some of the presently preferredembodiments of this invention. Various other embodiments andramifications are possible within it's scope. For example:

[0026] For stackable system board, it allows more expansion boards tofit into a particular space and can process more applications.

[0027] One system board can be designed with more than one shieldexpansion zones.

[0028] Additional heat sink may be necessary for the expansion boards,which generate high heat.

[0029] A system board may comprise multiple expansion zones on both sideof the PCB.

[0030] A system board may comprise different size of the expansion zone.

[0031] For special type of expansion boards, an expansion zone maycomprise more than one connector and other means to joint the expansionboards with the system board.

[0032] A shield expansion housing solution may have some holesconducting circuit from inside to outside.

[0033] Thus the scope of the invention should be determined by theappended claims and their legal equivalents, rather than by the examplesgiven.

What is claimed is:
 1. A computer system board with plularity of shieldexpansion housing solution for add-on expansion boards comprises: a) acomputer system board; b) plurality of shield expansion housingsolution.
 2. The shield expansion housing solution of claim 1 comprisesa shield expansion zone on the system board and a corresponding metalhousing cover.
 3. The shield expansion zone of claim 2 comprisesexpansion connect means and the expansion PCB zone.
 4. The expansion PCBzone of claim 3 is a ground shield copper plate PCB area.
 5. The metalhousing cover of claim 2 is a metal housing which is capable to coverthe expansion board and the corresponding expansion PCB zone of claim 3underneath it.
 6. The metal housing cover of claim 2 is mounted on thecomputer system board after an expansion board is connected to theshield expansion zone of claim 2.